Yes animation nodes is the way to go.
For instance, I can define a single action in the NLA editor for an object then delay the same action for its clones, notice how each clone has different colors, so they aren’t just dumb copies, and no baking.
While you can do the same procedurally in geo nodes with indexes, good luck doing that when the movement has 30 different steps with keyframes on different tracks…
Also Animation nodes has direct support for bones and poses
Geo nodes is better at working on meshes, while animation nodes is really for animating stuff mograph style, quickly.